US3905211A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for detecting defects in needles
Assignee: Institut Français du Textile et de l'Habillement
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Filing: 1974-06-13
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Granted: 1975-09-16
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Expires: 1994-06-13
Abstract
Abstract An apparatus for detecting faulty needles on an operating loom, particularly an operating hosiery loom. The apparatus comprises at least one magnetic detector, for example a Hall effect probe, mounted so that the needles of the loom pass successively in front of it during operation of the loom, and an associated electronic circuit for receiving signals from the or each detector, identifying those signals indicative of a defective needle, and providing a control signal for stopping the loom when such a signal is identified.
Inventors
- 👤 Jean-Pierre Raisin
- 👤 Bernard Helffer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:33
CPC Classifications
D; D04; D04B; D04B35/00; D04B35/10; D04B35/18
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
224 words
An apparatus for detecting faulty needles on an operating loom, comprising: magnetic detecting means mounted so that the needles of the loom pass successively in front of it during operation of the loom, for producing signals of a normal amplitude when non-defective needles pass in front of it, signals of greater than normal amplitude when a first class of defective needles pass in front of it and signals of smaller than normal amplitude when a second class of defective needles pass in front of it; a first electronic circuit connected to said magnetic detecting means for identifying signals of greater than normal amplitude indicative of a defective needle, and for providing a first control signal for stopping the loom when said defective needle is detected; and a second electronic circuit connected to said magnetic detecting means for identifying signals of smaller than normal amplitude indicative of a defective needle, and for providing a second control signal for stopping the loom when said defective needle is detected, said second electronic circuit comprising means for producing a first output signal in response to signals which are not of smaller than normal amplitude, and for producing a second output signal in response to the absence of signals which are not of smaller than normal amplitude, during a time interval dependent on the operating speed of the loom.
Claim 2
Independent Claim
224 words
An apparatus for detecting faulty needles on an operating loom, comprising: magnetic detecting means mounted so that the needles of the loom pass successively in front of it during operation of the loom, for producing signals of a normal amplitude when non-defective needles pass in front of it, signals of greater than normal amplitude when a first class of defective needles pass in front of it and signals of smaller than normal amplitude when a second class of defective needles pass in front of it; a first electronic circuit connected to said magnetic detecting means for identifying signals of greater than normal amplitude indicative of a defective needle, and for providing a first control signal for stopping the loom when said defective needle is detected; and a second electronic circuit connected to said magnetic detecting means for identifying signals of smaller than normal amplitude indicative of a defective needle, and for providing a second control signal for stopping the loom when said defective needle is detected, said second electronic circuit comprising means for producing a first output signal in response to signals which are not of smaller than normal amplitude, and for producing a second output signal in response to the absence of signals which are not of smaller than normal amplitude, during a time interval dependent on the operating speed of the loom.
Claim 3
Dependent Claim
37 words
An apparatus according to claim 1, wherein said first electronic circuit comprises a first comparator circuit having a first input connected to said magnetic detecting means and a second input connected to a source of reference voltage.
Claim 4
Dependent Claim
15 words
An apparatus according to claim 2 wherein said first comparator circuit includes a Schmitt trigger.
Claim 5
Dependent Claim
109 words
An apparatus according to claim 1 wherein said second electronic circuit comprises a second comparator circuit for producing first pulses having a recurrent frequency equal to the frequency of said signals which are not of smaller than normal amplitude, and monostable circuit means having a first input connected to said second comparator circuit and a second input connected to electronic control means, said monostable circuit means being retriggerable and said electronic control means supplying a voltage dependent on the speed of operation of the loom to said monostable circuit means for making the triggering time of said monostable circuit means dependent on the speed of operation of the loom.
Claim 6
Dependent Claim
54 words
An apparatus according to claim 4 wherein said second electronic circuit further comprises second monostable circuit means responsive to said first pulses for producing second pulses having a recurrent frequency equal to the frequency of said first pulses and having constant amplitude and time-width, said second pulses being supplied to said electronic control means.
Claim 7
Dependent Claim
64 words
An apparatus according to claim 1 further comprising an ''''OR'''' gate having a first input connected to said first electronic circuit for receiving said first control signal, a second input connected to said second electronic circuit for receiving said second control signal and an output connected to an output circuit for producing a control signal of at least predetermined duration for stopping the loom.
Claim 8
Dependent Claim
36 words
An apparatus according to claim 1 wherein said magnetic detecting means includes at least a Hall effect probe, the active surface of which has a width less than the depth of the needles to be detected.
Claim 9
Dependent Claim
22 words
An apparatus according to claim 7 wherein said magnetic detecting means includes a plurality of Hall effect probes connected as a bridge.
Claim 10
Dependent Claim
35 words
An apparatus according to claim 1 wherein said magnetic detecting means includes at least a magneto-resistance detector the active surface of which has a width less than the depth of the needles to be detected.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |